硼组分在BaAl_2Si_2O_8∶Eu^(2+)发光材料中的作用

Spectral Properties in Boron Doped Phosphors BaAl_2Si_2O_8∶Eu^(2+)

采用高温固相法在弱还原气氛下制备Ba0.955Al2-xBxSi2O8∶Eu2+(x=0~0.5)系列荧光粉,研究B3+置换Al3+对晶体结构和光谱特性的影响。B3+以类质同相替代BaAl2Si2O8晶格中的Al3+形成部分连续固溶体,随着B3+置换量的增加,晶胞参数a,b,c和晶胞体积V呈线性递减,晶面夹角β呈线性递增。荧光激发光谱位于225~400 nm的宽带谱可拟合成4个峰,表观峰值位于337 nm,半峰全宽为96 nm。荧光发射光谱位于370~600 nm,可由423 nm和457 nm两峰拟合而成,表观峰值位于437 nm,两拟合峰峰位均随着B3+置换量的增加呈线性蓝移。

A series of phosphors Ba0.955Al2-xBxSi2O8∶Eu2＋（x=0～0.5） were prepared by solid-state reaction in weak reductive atmosphere.The lattice positions and the luminescent mechanism of Eu2＋ in the host were discussed.The effects of B3＋-substitution on the host lattices and spectral properties were also investigated.It was found that when B3＋ entered BaAl2Si2O8 lattice and substituted for Al3＋ complete solid solutions formed in the whole range of x=0～0.5.The lattice parameters（a,b,c） and unit cell volume of phosphors Ba0.955Al2-xBxSi2O8∶ Eu2＋（x=0～0.5） decreased linearly and lattice parameter β increased linearly as boron content increased.A broad excitation spectrum consists of four excitation bands,which locate between 225 nm and 400 nm,its peak wavelength is at 337 nm,and basically does not change with the content of B3＋.The full width at half maximum is 93 nm.The emission spectrum is also a broad band between 370 nm and 600 nm and its apparent peak is at 437 nm,which can be fitted by two peaks at 423 nm and 457 nm.Two fitted peaks are blue shifted with the increasing of the content of B3＋-substitution.